Can stacking machine



J. socKE CAN STACKING MACHINE May 24, 1949.

Filed uarn so, 1945 3 Sheets-Sheet 1 INVENTOR.

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CAN STACKING MACHINE 4 Filed March 30, 1945 3 Shets-Sheet 2 M BMM 2m M lm;

May 24, 1949. J, E socKE 2,470,795

CAN STACKING MACHINE Filed March 30, 1945 3 Sheets-Sheet; 5

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TTOEN'YS I Patented May 24, 1949 CAN STACKING MACHINE John E. Socke, Pelham Manor, N. Y., assignor to American Can Company, New York, N. Y., a corporation of New Jersey Application MarchA 30, 1945, Serial No. 585,665

11 Claims. 1

The present invention relates to a machine for stacking containers or ycans and has particular reference to mechanism for positioning the cans in a predetermined arrangement for packing into paper bags prior to shipment or storage.-

Empty cans-are usually shipped and stored in sealed paper bags for convenience in handling and to keep the cans clean during transportation. For best results in making a rm and compact package, the cans are arranged in the bag in an orderly manner, the cans being stacked in a plurality of layers. The arrangement and number of cans in each layer depends entirely upon the size of the cans being packed. Such anarrangement in each layer may be a plurality of rows of an equal number of cans in each row in `a staggered or straight layout or may be rows of an unequal and an equal number of cans in each alternate row and in a staggered layout.

The instant invention contemplates a mechanism for arranging the cans in a staggered layout of a plurality of rows having an unequal and an equal number of cans in alternate rows.

An object of the invention is the provision of a mechanism for placing cans in a predetermined arrangement for packing into paper bags for shipment and storage wherein the cans are received in a moving procession and are segregated into rows having an unequal and an equal number of cans in each alternate row and the rows formed into a staggered layout or arrangement, best tted as to economy of space and compactness, to be transferred as a unit layer into the bag.

Another object is the provision of such a mechanism wherein rows of equal and unequal numbers of cans may be alternately segregated so that a desired pattern of can arrangement may be obtained to form a staggered layout.

Another object is the provision of a mechanism of this character wherein the rows of cans alternating in equal and'unequal numbers are arranged in a staggered layout in proper sequence and in timed order so that the desired can pattern will result.

. Numerous other objects, and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

. Figure 1 is a top plan view of a machine embodying the instant invention, with parts shown insection and with parts broken away, the view including a wiring diagram of the electric apparatus used in the machine;

Fig. 2 is a sectional view taken substantially along the line 2-2 in Fig. 1; and

Figs. 3 and 4 are views similar to Fig. 1, with certain of the movable parts in diierent positions.

As a preferred embodiment of the instant invention the drawings illustrate a machine in which cylindrical cans A are stacked into a loading tray B in a staggered layout asl shown in dotted lines in Fig. 1 so that they may be trans-` ferred in any suitable manner, as a unit layer into a paper bag for shipment or storage.

The cans to be stacked are received in processional order moving in a straight line along a runway which includes a pair" of spaced and parallel guide rails II (Fig. 1). The cans are in an upright position and are supported on a continuously moving belt conveyor I2 which is disposed between the guide rails. The belt carries the cans into the machine along a straight line path of travel extending between the loading tray B and a pusher or segregating member I3 which is located in front of the tray. A stop element Id disposed adjacent a side of the tray (at the right as viewed in Fig. l) stops the line of cans entering the machine in a predetermined position relative to the tray in readiness to be pushed into the tray by the pusher I3.

The loading tray B is rectangular in shape and is of suicient dimensions to hold al full unit layer of cans A. In the instant case, by Way of example, the tray is designed to hold six rows of cans in staggered arrangement, the first row containing six cans, the second row five cans and thus alternating for the full six rows.

The front of the tray B is open, while its other three sides are formed with upright retaining walls l1, I 8, I9. The bottom of the tray is supported on a machine frame 2| and is formed with a pair of spaced and parallel depending slide rails 22 which operate in longitudinal slide ways 23 formed in the top of the machine frame. v

To receive alternate rows of cans of equal and unequal numbers in staggered or nesting relation, the loading tray B is shifted sidewise, longitudinally of the machine for each row of cans to be received and in time with the reception of the cans. For this purpose the machine is equipped with a pair of air operated or pneumatic tray cylinders 26, `2l. These cylinders are secured to the top of the frame 2|, adjacent-the respective retaining walls l1, I9 of the tray;

The tray cylinder 28 constitutes a pneumatic cushioning device and is provided with a piston 3l having a rod 32 which is secured to the retaining wall I1 of the tray. The outer end of the cylinder is connected to a pipe 33 which constitutes an air line and which leads from any suitable source of compressed air. The air continuously exerts its pressure against the piston 3| and thus tends to force the tray toward the right as shown in Fig. 1 and to maintain it in this position against a stop pin 35 secured in the top of the frame 2|. This is the position of the tray when it receives a row of six cans.

The tray cylinder 21, disposed adjacent the opposite side of the tray B, is of considerably larger diameter than the cylinder 26 and constitutes a pneumatic ram. The cylinder 21 is provided with a corresponding larger diameter piston 31 having a rod 38 which is secured to the retaining wall I9 of the tray. The outer end of this cylinder is connected by an air pipe 39 to a valve housing 4I. The housing is formed with an air channel 42 which at one end communicates with the air pipe 39 and which at the opposite end communicates with a pipe 43. One end of the pipe 43 is secured in the housing while its opposite end connects with and receives air from the main air line pipe 33.

'I'he valve housing 4| encloses a slide valve 44 which extends across the air channel 42 and which normally closes oi the channel so that the air from the line 33 is prevented from entering the cylinder 21 when the tray is in the position shown in Fig. 1. 'I'he valve is formed with an actuating stem 46 which is connected to the movable core of a normally deenergized electric solenoid 41 indicated in the Wiring diagram. A compression spring 48 in the solenoid presses against its core and `normally keeps the air valve closed.

The valve stem 46 is also connected to a lever 49 which is pivoted on a lug 5I formed on the valve housing 4I. The opposite end of the lever carries a vent cap 52 which is adjacent avent port 53 formed in the housing. This vent port communicates with the air channel 42.

,When the tray solenoid 41 is energized, by electric circuits hereinafter explained, it shifts the valve 44 to open position and closes the vent port 53 in the valve housing 4| and thus` permits compressed air from the main air line The tray remains in this position as long as the valve 44 stays in open position.

After the tray has received a short row of cans, the solenoid 41 is deenergized and the spring 48 thereupon pushes the valve 44 into closed position. This cuts olf the supply of air to the large tray cylinder 21. This same movement of the valve opens the vent port 53 and thus releases the air in the large cylinder. With the large cylinder thi-ls opened to the atmosphere, the compressed air acting against the piston in the small cylinder immediately returns the tray to its original position, as shown in Fig. 1, in readiness to receive another long row of six cans. In this manner the tray is shifted laterally through successive alternating strokes into a position to receive a long row of cans and then into a position to receive a short row until the tray is completely lled. The entire unit layer of cans is then removed in their staggered relation in one batch. in any suitable manner.

The stop element I4 which stops the line of cans entering the machine in the proper location relative to the tray for deposit thereinto, moves with the tray in order to eiect this operation, although it should be understood that the stop element could be actuated equally well by any other means as long as it shifts in time with the tray. The stop element I4 is disposed in longitudinal alignment with the path of travel of the cans A entering the machine and is formed on the inner end of a rod 6| (Fig. 1), loosely carried in a slide bar 62 which rests on and slides along a slide plate 64 bolted to the top of the main frame 2l.

A compression spring 66 surrounding the stop rod and interposed between the stop element and the slide bar forms a yieldable connection between these two parts. The travel of the rod within the slide bar is limited by a collar 61 which is carried on the outer end of the rod. The outer end of the rod also carries a movable switch element 68 of a normally open actuating electric switch 69 having contacts 1I, 12. This switch is mounted on a pad 13 formed on the slide bar 62 and thus moves with the bar.

The slide bar 62 is connected to the inner ends of a pair of spaced and parallel actuating arms 15, 16 which constitute a parallelogram mounting disposed adjacent the retaining Wall I9 of the loading tray B The outer ends of the arms are mounted on pivot studs 11 threadedly secured in the top of the main frame 2|. The arm 16 intermediate its length is connected by a link 18 to the retaining side wall I9 of the tray.

Hence as the tray B shifts from side to side to receive long and short rows of cans, the arms 15, 16 rock on their pivot studs 11 and thus shift the slide bar 62 and its stop element I4 in time with the tray and in the same direction. The stop element I4 is normally located so that when the tray is in position to receive a long row of cans (which just fills the width of the tray) its can engaging face is substantially flush with the inside surface of the retaining wall I9 of the tray (Fig. l).

When the tray B shifts toward the left a distance equal to substantially one-half the diameter of a can (as viewed in Fig. 1) into a position to receive a short row of cans which will be in nested or staggered relation to the long row, the stop element I4, through its connection with the tray, moves inwardly or to the left a distance equal to the full diameter of a can to be stacked (Fig. 4). With the stop element in this position the line of incoming cans is stopped a half a can diameter short of the inner surface of the retaining wall I9 of the tray and hence these cans will be in a staggered relation to the long row which is already in the tray, also as best seen in Fig. 4. In this manner a different number of cans are in alternate rows and this is elected l merely by the shifting of the stop element with one behind the other until a line of sufdcient length to overcome the resistance oi the spring 9S is assembled. When such a line is created the pressure of the cans against the stop element Il will shift the stop element sufficiently to close the electric switch 69 and this establishes certain electric circuits, shown in the wiringdiagram, to set the pusher member I3 in operation to insert the cans into the tray.

The pusher member i9 extends for nearly the full width of the loading tray B and is disposed in an elevated position so that it can move across .the can belt conveyor I2 and clear the conveyor and the stop element i6 when positioned for a short row of cans, without interference. The pusher is mounted on the inner ends oi a pair Aof spaced and parallel support bars 82, 83 (Fig.

89 which is connected by a pair of spaced, long shoulder'bolts 9i to the pusher member i3.

I'he piston 8l is reciprocated within the cylinder by compressed air acting against one or both faces of the piston. For this purpose air is continuously introduced into the inner end of the cylinder by a'pipe 92 which connects with the main air line 33 and receives compressed air from this line. Compressed air under the same pressure is also introduced, periodically, into the outer end of the cylinder by way of a short pipe 93 which is connected into a valve housing 9d. The valve housing is also connected by way of a pipe 95 to the pipe 92.

The valve housing 99 is similar to the valve housing di and is formed with an air channel 96 which communicates with the housing ends of the pipes 93, 95. The channel also communicates with an atmosphere vent port 91 formed in the housing. The channel is normally closed of.F by a slide valve 98 which extends across the channel. This valve is formed on a rod 99 which is connected to a movable core of a normally deenergized electric solenoid IUE which is included in the circuits shown in the lwiring diagram in Fig. 1.

A compression spring I 92 housed within the solenoid IOI presses against its core and thus keeps the valve in closed position when the solenoid is deenergized. The valve rod 99 is also connected to a lever IIN which is pivotally mounted on the valve housing and which carries on its opposite end a vent cap |95 for closing the .vent port 91 when the valve is open.

Hence compressed air continuously admitted into the inner end of the cylinder 86 acts against the inner face of the piston 81 to keep the pusher in its normally retracted position. When a row by the cross sectional area of the piston rod.

of cans is to be segregated from the line of incom- Therefore the force against the outer face is greater than that against the inner face and thus thepiston is4 moved inwardly in the cylinder;- This movement of the piston'iorces the pusher I3 against the cans on the conveyor belt I2 and thus shifts them from the belt into the loading tray B and leaves them just inside the edge of the front of the tray.

The pusher member I9 only pushes into the tray those cans which are disposed in front oi the pusher end which are in line with the tray.

During this inserting operation a stop projection |06 formed yon the left side of the pusher (as viewed in Fig. 1) moves in front of the cans remaining on theconveyorand holds them back until the pusher is withdrawn for the next inserting stroke. It should be noticed that the outer edge of this stop projection is disposed in a line extending just inside the inner surface of the retaining wall Il of the tray. This is so that the pusher will engage all the cans when a long row is to be pushed into place and will cut o the last can in the line when the tray B and the stop element It are shifted a half can diameter and a full can diameter respectively, for a short row of cans. o

When the row of cans. inserted into the tray B is fully in place, the pusher solenoid lili is deenergized and its spring I02 shifts the valve into' Y of the pusher and to engage against the movable stop element It. On subsequent inserting strokes of the pusher i3 the cans being inserted into the tray engage against those previously positioned in the tray and thus push the positioned cans toward the rear of the tray until the entire tray is filled.

A movable or depressible guide rail IIi is disposed in frontoi the pusher member I3 and forms a continuation of one of the conveyor guide rails II to keep the incoming cans in a straight line as they enter into the space between the tray and the pusher. This guide rail is disposed in a slot I I2 formed in the top of the main frame 2| and is carried on a vertical support rod H3 (Fig. 2) which slides in a bearing II4` formed on the frame. The lower end of the rod is connected to a movable core IIS of a normally deenergized electric solenoid I'I 6 secured to the frame. A compression spring housed within the solenoid and acting against the lower end of the core keeps the guide rail I II in a. normally raised position to guide the incoming cans.

Just prior to a can pushing stroke of the, pusher member I3, the guiderail solenoid II6 is energized and this draws the guide rail III downwardly in its slot H2 so that the cans being inserted into the tray will clear the rail without interference. to its normal retracted position the guide rail solenoid is deenergized and lits spring returns the vrail to guiding position for the incoming cans.

Reference should now lbe had to the wiring diagram in Fig. 1. The cycle of operation of the machine is started by the closing of the stop ele-` When the pusher'member returns Aarroyos ment switch 69 which is effected by the line of cans entering the machine, as hereinbefore explained. The loading tray B is in the position shown in Fig. 1 and thepusher member I3 is in its normal retracted position. The stop switch 69 forms a part of a relay circuit D which includes a pair of double pole electric switches |2|, |22 having movable elements |23, |24 respectively which are actuated by the loading tray B. When the tray is in the position shown in Fig. 1 the movable element |23 closes against a pair of contacts |25, |26 and the movable element |24 closes against a pair of contacts |21, |28. When the tray shifts townrd the left into the position shown in Fig. 4 the movable element |23 closes against a pair of contacts |3|, |32 and the movable element |24 closes against a pair of contacts |33, |34.

The relay circuit D further includes a triple pole cam operated switch |36 and a relay |31. The triple pole switch is equipped with two movable elements |38, |39. This circuit as well as all the other circuits to be hereinafter described receive electric energy from a generator circuit which includes a generator |4| connecting with a main lead wire |42 and a return lead wire |43.

When the stop switch 69 closes, through the pressure of the cans A on the belt conveyor I2 pressing against the stop element r|4 and connected parts, electric energy from the main lead wire |42 flows through the relay circuit D along a wire |45 connecting the lead wire |42 with the contact |25 of the tray switch |2l|. This energy passes along the switch element |23, contact |26, connecting wires |46, |41 to contact |21, switch element |24 and contact |28 of the tray switch |22, a wire |48 and contact |34 also of switch |22, a connecting wire |49 to contact 1| of the stop switch 69, through the switch element 68, contact 12, a connecting wire to the relay |31 and thence by way of a wire |52 to the main return lead wire |43.

Electric energy passing along this relay circuit D energizes the relay |31`and this establishes three new circuits, a guide rail circuit E, a pusher actuating circuit F and a holding circuit G. For this purpose the relay is formed with three movable switch elements |55, |56, |51 which close against switch contacts to simultaneously establish these three circuits.

Switch element |55 of the energized relay |31 closes against a pair of contacts |58, |59 which establishes the guide rail circuit E. Electric energy then ows from the main lead wire |42 along a connecting wire |6|, through a pair of contacts |62, |63 and movable element |38 of the cam operated switch |36, a connecting wire |64 to and through4 the guide rail soleniod ||6, a connecting wire |65, through contacts |58, |59 and switch element |55 of the relay |31 and thence by a wire |66 to the return lead wire |43. Electric energy passing along this circuit energizes the guide rail solenoid ||6 and thus pulls down the guide rail clear of the cans on the belt conveyor l2, as hereinbeiore explained.

In the pusher actuating circuit F, the movable element |56 ofv the energized relay |31 closes against-a pair of contacts |1|, |12 to establish this circuit. With this switch closed, electric energy from the main lead wire |42 passes along a connecting wire |13, contacts |1|, |12 and element |56 of the relay |31, a connecting wire |14 to and through the pusher valve solenoid |0|, and thence by a connecting wire to the return lead wire |43. Electric energy passing along this circuit energizes the valve solenoid |6| and thus shifts the valve 98 to open position and admits air intothe pusher cylinder 86 to actuate the pusher |3 through an inward or can pushing vstroke as hereinbefore explained.

The holding circuit G is established to hold the guide rail circuit E and the pusher actuating circuit F closed during the full inward movement of the pusher member I3' since during this movement the cans are shifted out of engagement with the stop element |4 and this allows the stop switch 69 to open. Without the holding circuit G, the opening of the stop switch would immediately deenergize the other circuits.

To establish the holding circuit G the movable element |51 of the relay |31 closes against a pair of contacts |11, |18. With this switch closed electric energy from the main lead wire |42 passes along the connecting wire IBI, through contacts |62, |63 and element |38 of the cam operated switch |36, a connecting wire |19, through contacts |11, |18 and element |51 of the relay |31, a connecting wire |86, through the relay |31 and thence through the wire |52 to the return lead wire |43. Electric energy passing along this circuit keeps the relay |31 energized after the stop switch 69 opens as above mentioned.

When the pusher member I3 has reached the end of its can pushing stroke, i. e., when the cans are in fully inserted position in the loading tray B, as best shown in Fig. 3, all three circuits E, Fand G are broken simultaneously to return the pusher member I3 and the guide rail to their original positions in readiness for the assembling and transfer of another row of cans. This is brought about by cam action. For this purpose the pusher support rod 83 carries a tapered cam |82 (Fig. 1) which moves with the rod.

When the pusher i3 nears the end of its inward stroke the cam |82 rides under a roller'l83 carried by the movable elements of the switch |36 and forces the roller and its attached switch elements outwardly. This cam action moves the switch element |38 of the switch |36 away from its contacts |62, |63 and thus breaks the holding circuit G. This deenergizes the relay |31 and thus opens all the relay switches |55, |56, |51. Hence all circuits are broken. The spring |02 in the pusher solenoid |0| returns the valve 98 to closed position and opens its vent port 91 to allow the pusher |3 to return to its retracted position and the spring in the guide rail solenoid I6 returns the guide rail to can engaging and guiding position, as explained above.

When the switch element |38 of the cam operated triple pole switch |36 moves away from the contacts |62, |63 it momentarily closes against a pair of contacts |85, |66 of the switch |36 which establishes an auxiliary relay circuit H which includes a portion of the main relay circuit D. This auxiliary relay circuit includes an auxiliary relay |81 having two movable switch elements |88, |89.

While the switch element |38 of the switch |36 is closed against the contacts |85, |86, electric energy from the main lead wire |42 passes along the wire |45 of the main relay circuit D, contacts |25, |26 and switch element |23 of the tray switch, a connecting wire |9|, through contacts |85, |86 and switch element |38 of the switch |36, a connecting wire |92, auxiliary relay |81, a connecting wire |93, and thence by wire |52 to the return lead wire |43. Electric energy flowing along this circuit energizes the auxiliary relay |81.

Energization of the auxiliary relay |81 closes its movable element |88 against a pair of contacts |95, |96 of a normally open holding circuit K which cuts out the cam operated switch |36 and also the tray switch contacts |25, |26 and |21, |28. Thus electric energy from the main lead wire |42 passes along a connecting Wire |91, normally closed contacts |98, |99 and a movable switch element 20| of a normally deenergized breaker relay 202, a wire 203 connecting contact |99 with contact |95, contacts |95, |96 and switch element |88 of the auxiliary relay |81, a wire 204, auxiliary relay |81, and wires |93, |52 returning to the return lead wire |43. Electric energy passing through this holding circuit -K keeps the auxiliary relay |81 energized when the cam |82` on the pusher support rod 83 moves away from the switch roller 83 and thus shifts the switch element |38 of switch |36 away from the contacts |85, |88 and returns it to closing position against the contacts |62, |83.

The energization of the auxiliary relay |81 also closes its switch element |89 against a pair of contacts 2| 2|2 and this establishes a tray shifting circuit L which includes the tray air valve solenoid 61. Thus while the auxiliary relay |81 is energized electric energy passes from the main lead wire |42 along the wire |6|, a connecting wire 2|3,contacts 2| I, 2 I2 and switch element |89 of the auxiliary relay |81, a connecting wire 2|4, tray solenoid 41, and thence returning along a connecting wire 2|5 to the return lead wire |43.

Electric energy passing along this tray shifting circuit L energizes the tray solenoid 41 and this shifts the tray air valve 44 into open position and th-us admits air into the cylinder 21 to shift the loading tray B and the stop element I4 into the position shown in Fig. 4 to locate and receive a short row of cans as hereinbefore explained. The

` ary against the cushion of air in the small cylinder 26 and this is the proper position toreceive the short row of cans.

Locating and pushing the short row of cans into the loading tray B as shown in Fig. 4 is effected in the same manner. as for the long row and is brought about by the same circuits E, F and G which are used for the long row of cans. It should be noted, however, that when the tray is in the short row position shown in Fig. 4, the tray switch element |23v (Fig. 1) is away from the contacts |25, |26 and is closed against the contacts |3|, |32 of this switch. Also the tray switch element |24 on the opposite side of the tray is spaced from the contacts |21, |28 of this switch and is against the contacts |33, |36.

Hence the relay circuit D used for energizing the main relay 31, to draw down the guide rail through its solenoid ||6 and also to operate the air valve 98 on the pusher air cylinder through its solenoid now includes the contacts |3|, |32, and |33, |34 of the tray switches |2|, |22 instead of the contacts |25, |26, and |21, |28 in those switches.

Electric energy for energizing the relay |31 noW passes from the main lead wire |42 along wire |45 of the relay circuit D, a connecting wire 22 contacts |3|, |32 and switch element |23 of the tray switch |2|, connecting wires 222,223, contacts |33, |34 and switch element |24 of the tray switch |22, wire |49, contacts 1|, 12 and switch element 68 of the stop switch 69, wire |5|, relay 10. 31, and wire` |52 to the return lead wire |43 as in the original relay circuit D,

Energ-ization of the main relay |31 through this new relay circuit D establishes the guide rail circuit E, the pusher actuating circuit F, and the holding circuit G in the same manner and for the same purpose also explained above. The only difference is that now a short row of cans is pushed into the tray instead of a long row.

When the short-row of cans is fully positioned within the tray as when the pusher reaches the innermost extent of its inward travel, the cam |82 again engages theswitch roller |83 and opens the switch |36, moving its switch element |38 away from the contacts |62, |63 to break the relay circuit D. `This deenergizes the guide rail solenoid H6 and the pusher air valve solenoid 0| and thus returns the guide rail and the pusher to their original positions as hereinbefore explained. l

There is one difference, however, that should be noted at this point in the operation of the electric apparatus and that is when the switch element |38 moves away from its contacts |82, |63 and closes against the contacts |85, |86as hereinbefore explained, the auxiliary relay circuit H is not effected because the tray switches |2|, |22 are not now closed against the contacts |25, |26 and |21, |28. These contacts are open and hence no circuit is completed. It will be remembered that the auxiliary relay-|81 is already energized and is being maintained in that condition by the holding circuit K which keeps the tray in positionto receive the short row of cans.

'Ihe loading tray B has now received its short row of cans and is therefore ready to be shifted back into its original position as shown in Fig. l to receive another long row of cans. This is 'brought about by the switch element |39 on the switch |36. This switch element closes against a pair of contacts 225, 226 in a breaker circuit M at the` same time the switch element |38 closes against the contacts |85, |86. This is only of momentary duration and is brought about by the cam |82. During the time the contacts 225, 226 are closed, electric energy from the main lead wire |42 passes along wire |45 of the relay circuit D, wire 22|, contacts |3|, |32 and switch element |23 of the tray switch 12|, wire 222, a connecting wire 228, breaker relay 202, contacts 225, 226 and switch element |39 of switch |36, returningalong a connecting wire 229 to the return lead wire |43.

Electric energy passing along this circuit en f ergizes the breaker relay 202 and moves its switch y the tray solenoid 41 is thus deenerg-ized. This permits the solenoid spring 48 to close the air valve 44 and open the vent 53 in the valve housing. The supply of air to the large tray cylinder 21 is thus cut off and the cylinder opened to atmosphere so that the air in the small cylinder 26 operates to shift the loading tray B back into the original position of Fig. 1.

The 'closing of the switch element |39 against the .contacts 225, 226 takes place every time the switch |36 is opened by the cam |82 on the pusher support bar 83. However, the closing ofv these contacts only operates to form the breaker ciril cuit M on every alternate stroke of the cam as when a short row of cans is to be inserted into the tray. This is when the tray switches |2|, |22 are closed across the contacts |3I, |32 and |33, |34. On other strokes of the cam, as when long rows of cans are being inserted into the tray, the tray switches |2I, |22 are closed across the contacts |25, |26, and |21, |28 and thus no circuit can be established which includes the breaker relay 2|l2- This completes the cycle of operation of the machine for inserting two rows of cans into the loading tray B, a long row of six cans and a short row of ve cans nesting in staggered relation thereto. The above explained operations are repeated for each set of two rows until the entire tray is filled with cans. The load of cans is then ready to be removed as a unit layer from the tray and placed in a paper bag for shipment or storage, but this forms no part of the present invention.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts Without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

1. A machine for stacking cans in staggered rows, which comprises in combination, conveyor means for propelling cans to be stacked along a straight line path of travel, a tray having means for movably mounting the same adjacent one side of said path of travel for receiving said cans, a reciprocable pusher member disposed adjacent the opposite side of said path of' travel for pushing a row of said cans transversely of said path of travel and into said tray, and means for shifting said tray in opposite directions relative to and longitudinally of said path of travel in time with the reception of each row of cans. the tray thereby receiving adjacent rows of cans in staggered relation.

2. A machine for stacking cans in staggered rows, which comprises in combination, conveyor means for propelling cans to be stacked along a straight line path of travel, a tray having means for movably mounting the same adjacent one side of said path of travel for receiving said cans, a reciprocable pusher member disposed adjacent the opposite side of said path of travel for pushing a row of said cans transversely of said path of i travel and into said tray, means movable with said pusher member for holding back a line of cans on said conveyor means while a row of cans is being pushed into said tray, and means for shifting said tray in opposite directions relative to and longitudinally of said path of travel in time with the reception of each row of cans, the tray thereby receiving adjacent rows of cans in staggered relation.

3. A machine for stacking cans in staggered rows, which comprises in combination, conveyor means for propelling cans to be stacked along a straight line path of travel, a tray having meansfor movably mounting lthe same adjacent one side of said path of travel for receiving said cans, a reciprocable pusher member disposed adjacent the opposite side of said path of travel for pushing a row of said cans transversely of said path of travel and into said tray, a depressible guide rail located between said pusher member and said tray for guiding the cans into place adjacent said pusher member, means for depressing said guide rail in advance of a can inserting movement of said pusher member, and means for shifting said tray in opposite directions relative to and longitudinally of said path of travel in time with the reception of each row of cans, the tray thereby receiving adjacent rows of cans in staggered relation.

4. A machine for stacking cans in staggered rows, which comprises in combination, conveyor means for propelling cans to 4be stacked along a straight line path of travel, a movable tray disposed adjacent one side of said path of travel for receiving said cans, a reciprocable pusher member disposed adjacent an opposite side of said path of travel for pushing said cans in rows transversely of said path of travel and into said tray, a stop element disposed in the path oftravel of said cans and movable with said tray for stopping the cans in a predetermined position relative to said tray so that alternate rows of cans segregated by said pusher member will have a different number of cans in the row than in the inbetween rows, and means for shifting said tray in opposite directions relative to and longitudinally of said path of travel in time with the reception of each row of cans for receiving the rows of cans in a staggered relation so that the cans of one row will nest with the cans of adjacent rows to provide a compact can formation in said tray.

5. A machine for stacking cans in staggered rows, which comprises in combination; conveyor means for propelling cans to be stacked along a straight line path of travel, a movable tray disposed adjacent one side of said path of travel for receiving said cans, a pusher member disposed adjacent an opposite side of said path of travel for pushing said cans in rows transversely of said path of travel and into said tray, a stop element disposed in the path of travel of said cans, a lever arm connecting. with said stop element, a link connecting said lever arm with said tray for shifting said stop element longitudinally of the path of travel of said cans and in time with the movement of said tray for stopping the cans in a predetermined position relative to said tray so that alternate rows of cans segregated by said pusher member will have a different number of cans in the row than the nbetween rows. and means for shifting said tray longitudinally of said path of travel after the reception of each row of cans for receiving the rows of cans in a staggered relation so that the cans of one row will nest with the cans of adjacent rows to provide a compact formation.

6. Ay machine for stacking cans in staggered rows, which comprises in combination, conveyor means for propelling cans to be stacked along a straight line path of travel, a tray having means for movably mounting the same adjacent one side of said path of travel for receiving said cans, a reciprocable pusher member disposed adjacent an opposite side of said path of travel for pushing said cans in rows transversely of said path of travel and into said tray, means for shifting said tray in opposite directions relative to and longitudinally of said path of travel in time with the reception of each row of cans for receiving the rows of cans in a staggered relation so that the cans of one row will nest with the cans of adjacent rows to provide a compact formation, and stop means disposed adjacent the path of travel of said tray for limiting the movement of said tray and for locating it in a predetermined position to receive the rows of cans in staggered relation.

7. A machine for stacking cans in staggered rows, which comprises in combination, conveyor means for propelling cans to be stacked along a straight line path of travel, a tray having means for movably mounting the same adjacent one side of saidpath of travel for receiving said cans, a

reciprocable pusher memberdisposed adjacent an opposite side of said path of travel for pushing said cans in rows transversely oi said path of.

travel and into said tray, and pneumatic devices operating against opposite sides of said tray for shifting said tray in oppositedirections relative to and longitudinally of said path of travel in time with the reception of each row of cans for receiving the rows of cans in a staggered relation.

8. A machine for stacking cans in staggered' rows, which comprises in combination, conveyor means for propelling cans to be stacked along a straight line path of travel, a tray having means for movablymounting the same adjacent one side of said path of travel for receiving said cans, a reciprocable pusher member disposed adjacent an 1 opposite side of said path of travel for pushing ception of a row of cans, said cushioning devicebeing further operable to thereafter shift the tray in the opposite direction longitudinally of the path of travel of the cans, whereby to insure a different number of cans in alternate rows of staggered relation so that the cans of one row will nest with those of adjacent rows to provide a compact formation.

9. A machine for stacking cans in staggered rows, which comprises in combination, conveyor means for propelling cans to be stacked along a straight line path of travel, a tray having means for movably mounting. the same adjacent one side of said path of travel for receiving said cans, a pusher member disposed adjacent an opposite side of said path of travel for pushing said cans in rows transversely of said path of travel and into said tray, a pneumatic cushioning device operable against said tray for'holding it in position to receive certain rowsof cans, a pneumatic ram operable against an opposite side of said tray'for shifting said tray longitudinally of the path of travel of said cans and against the resistance of said cushioning device forpositioning the tray for the reception of alternating rows of cans. valve and vent means connecting with said ram for admitting and releasing air to and from said ram for shifting said tray, and means for actuating said valve and vent means in time with the operation of said pusher member.

10. A machine for stacking cans in staggered rows, which comprises in combination, conveyor means for propelling cans to be stacked along a straight line path of travel, a tray having means for movably mounting the same adjacent one side of said path of travel for `receiving said cans, a reciprocable pusher member disposed adjacent an opposite 'side of said path of travel for pushing said cans in rows transversely of said path of travel and into said tray, pneumatic means for actuating said pusher member, and pneumatic devices operating against opposite sides of said tray for shifting said tray in opposite directions relative to and longitudinally of said path of travel in time vwith the reception of each row of cans so that the cans of one row will nest with the cans of adjacent rows and in staggered relation to provide a compact formation.

l1. A machine for stacking cans in staggered rows, which comprises in combination, conveyor means for propelling cans to be stacked along a straight line path of travel, a tray having means for movably mounting the same adjacent one side of said path of travel for receiving said cans, a pusher member disposed adjacent an opposite side of said path of travel for pushing said cans in rows transversely of said path of travel and into said tray, a depressible guide rail located between said pusher member and said tray for guiding the cans into place adjacent said pusher member, an electric solenoid connecting with said guide rail and operable in time with the said pusher member for depressing said guiderail in advance of 'a can inserting movement of said pusher member, and means for shifting said tray longitudinally of said path of travel after the reception of each row of cans for receiving the rows of cans in a staggered relation so that the cans of one row will nest with the cans of adjacent rows to provide a compact formation.

` JOHN E. SOCKE.

REFERENCES CITED The following references are of recoid in the file of this patent:

UNITED STATES PATENTS Rooney Apr. 28, 1942 

